/**
 * Created by Administrator on 2015/12/28 0028.
 */
object extends_struct {

  def main(args: Array[String]) {
    val w=new week1
    print(w.days.length)
  }
}
class month1{
  val num=31
  var days=new Array[Int](num)
}
class week1 extends { override val num=7} with month1{
//  override  val num=7
}